Question

why carbon make only one Bond double bond triple Bond but not 4 bond...as it has 4 free electrons so it can share all 4 with any other atom​

Answer 1

To take the 4 electrons of carbon there will be more more energy is needed because these electrons are near to nucleus

Answer 2

Diamond and graphite aren made with pure carbon, no other atoms included. The reason a carbon atom cannot bond with four electrons with another carbon is due to the carbon electron orbitals. Since it has a s and 3 p orbitals, it must create one sigma and at most 2 pi bonds with another carbon.